Well pump



eP 10, E. c. OVERALL 2,214,343

WELL PUMP Filed May 27, 1938 INVENTOR. [IQ/V557 C OVER/41L M jwgwATTORNEYS.

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Patented Sept. 10, 1940 PATENT OFFICE WELL 'PUMP Ernest 0. Overall,Gonzales, Tex.,

assignor of forty-five per cent to 0. S. Petty, San Antonio, Tex., andfifty-five per cent to J. H. Robertson, Hillsboro, Tex.

v Application May 27,1938, Se1;ia1 No. 210,450 4 Claims. 161. 193-5)This invention relates to pumps, particularly the pressure from the tube2 to be cut off from for the pumping of. oil and water wells, and of atype described in applicants co-pending application, filed May 27, 1938,Serial Number 203,785. The principal object of the invention is toprovide a pump of this nature whereby the usual sucker rods areeliminated. I

A further object of the invention. is the provision of apump whereby gasor air or a mixture 10 of both gas and air may be utilized for operatingthe pump in one direction of its stroke, thereby causing the fluid ofthe well to be elevated, and which power when released will continue toelevation of said fluid, thereby'attaining the-benefit on both theup-stroke and down-stroke of the pressure built up. l e v A stillfurther object of the invention is the means employed for equalizing thewell fluid pressure on both sides of the plunger piston, whereby theup-stroke of the pump is accomplished with a minimum of power. 4

Other minor, yet important objects of the invention ,will becomeapparent from a perusal of the followingdetailed description, taken inconnection with the accompanying drawing, and in the drawing:

Figure 1 is an elevational view in vertical section of the pumpembodying the invention, showing the pump mechanism on the extremedownward stroke; J Figure 2 is a view similar to that of Figure l, butillustrating the mechanism of the pump with the piston on the extremeupward stroke;

Figure 3 Ban enlarged cross-sectional view of l the pump, the view beinghad along the line 3-3 of Figure 1;

Figure 4 is a view similar to that of Figure 3, but showing across-section lower down and along the line 4-4 of Figure 2; and Figure5 is an enlarged detail fragmentary view in vertical section of thecheck valve in the top of the pump mechanism. p In the preferredembodiment of the invention as illustrated in the drawing, the numeral 1represents the casing of a well in-which the pump is to be operated. T

Mounted within the casing I is a tube-2, termed pressure tube, and whichcommunicates; with a source of power outside the well, and having its 50lower end extending down 'to a point near the fluid or'submerged in thefluid of the well.

- Threadedly or otherwise connected to the lower end of the tube 2 is acylinder 3, termedpressure cylinder, the upper portion of this cylinderbe- 55 ing reducd in diameter. Since for the most successful operationof the pump it is necessary for the cylinder 3 at provided intervals, aplug 4 is disposed in the top of the cylinder 3 for cutting off thenormal communication between the tube 2 and the cylinder 3. Then forcommunication purposes between this tube and the cylinder there .isprovided a passageway 5 leading to any desired point in the cylinder 3.'A plurality of such passageways 5 may be utilized as shown in Figures 3and 4, said passageways communicating with the cylinder 3 by means of anannularrecess 28 in this cylinder instead of having single ports foreach passageway. A slidable valve 33 is provided for cutting ofi thepressureof the tube 2 from the cylinder 3, thus eliminating thenecessity of a valve to be lifted against the pressure in the tube 2,such as a ball valve or the like,

since a slidable port type valve is easier to raise than a ball valvewould be.

On the bottom of the cylinder 3 is threadedly or otherwise secured asecond cylinder 6, commonly termed the working barrel of the pump. Aperforated mud tube l is connected to the bottom of the cylinder 6* by acoupling or union 8, this tube and form of connection being commonlyused in oil well equipment and which form no part of the invention.

In the bottom of the cylinder 6 is a conventional standing valve body ISwith a central bore I6, said valve body having a seat'l'l for a ballvalve 18, and. which permits the fluid from the well to pass up into thecylinder or pump barrel 6, but prevents its return into the well. A cage19 maintains this valve in operable position.

Since the well fluid is to be elevated to the surface through thecasing, a-pack-off 9 with a large 1 central bore is' disposed in saidcasing at any desired point and fits tightly against the walls of thecasing to prevent passage of fluid between the 40 casing and thepack-oil. Said pack-01f has a support 34 on which the cylinder 3 seats.With the cylinder 3 seated the fluid from the well must pass up throughthe pump barrel 6 to the cylinder 3, the pack-off separating the fluidin the well from the fluid that is being elevated. v A plunger rod 25reciprocates within the cyl-.' inders 3 and 6, and-connected to itslower end is 'a valved piston 20, which reciprocates in the cylinder 6.This valved piston 20 hasv a passage as shown and a seat 2| for a-ballvalve 22, the ball valve 22 being held in operable position by the cage23. This ball valve thus permits-fluid to pass upwardly, but preventsitsreturnto the Syvell or cylinder below said valve. inverted cup thepiston 20 ensure a tight relation between the cylinder or pump barrel 6and the piston in operation.v I

The plunger rod 25 has rigidly mounted thereon a plunger piston 26 withupwardly turned cups 21, these cups providing a fluid-tight relationbetween the piston and cylinder.

A coil spring 3|, or its equivalent, is operably associated with theplunger rod 25 for purposes hereinafter described. This spring is seatedon a washer 32, apertured for the passage of the plunger rod, the washerbeing supported on an annular shoulder as shown. The upper end of thespring 3| is held in position by a perforated washer 30 and a nut 30a,the washer30 being spaced from the plug 4 when the plunger rodis inuppermost position.

Slidably mounted on the plunger rod 25 and within the cylinder 3 is aport type valve 33, with openings 35. This valve is for the purpose ofcutting off and on pressure from the tube 2 to the cylinder 3, and foropening and closing pressure discharge port or ports 31 in the cylinder3.

A port or ports ID are provided in the lower part of the cylinder 3which communicate with fluid discharge passages II and permit elevationof fluid into the well casing. Disposed in the upper end of each ofthese passages is a check valve structure, consisting of a valve seat M,a ball valve I2 and a stop I 3, the latter maintaining the balll2'within the recess 12a in operable position.

The operation of the pump is as follows: Figure 2 of the drawing showsthe pressure piston 26 ready to begin its downward movement, called downstroke,for which gas, air or a mixture of both gas and air may beutilized--gas being preferable. By any suitable pressure pump, gas forinstance, is forced down the pressure tube 2, thence through thepassageway 5 and into the cylinder 3. The discharge port 31, as shown inFigure 2, is then closed. As additional gas is forced into the cylinder3, a pressure is built up therein, thereby forcing the piston 26downwardly. As the piston descends, the valved piston 20 likewise startsits descent. During this stage of the operation the ball valve I9 seats,while the ball valve l2 in the passage or passages II is raised from itsseat and fluid thereby passes up- Wardly. The fluid in the pump b'arrelor cylinder 6 does not change it position on the downward stroke of thepump, other than to move above the valved piston 20. As the piston 26nears its downward stroke, the stop 39 mounted on the plunger rod 25strikes the port valve 33, and as this valve is moved downwardly, thedischarge port 31 is opened, and the small annular recess 28 into whichthe passageway or passageways open, is closed. Simultaneously, thecompressed gas in the,cylinder 3 is allowed to escape through the port31 and into the column of fluid being elevated in the fluid elevationpassage II and which passes upwardly into the casing of the well.Immediately upon the opening of the, port 31, the pressure is equalizedon the upper and lower -sides of the piston 26, as some of thecompressedgas goes up into the casing, while some of it may go down thepassage II to some extent. As the pressure enualizes on both sides ofthe plunger piston 26, the back or static pressure of the column 'offluid in the casing closes the check valve I2, thereby cutting off theback or static pressure of the fluid in the casing from all cylindersbe-- low. As the pressure from the tube 2, and the static or backpressure of the column of fluid are in the cylinder 6 above the piston20 to be lifted in the cylinder 6. As the piston 20 moves upwardly, itcreates a suction, causing the fluid in the well to be pulled throughthe standing valve |5 up into the cylinder 6. In the event the cylinder3 is of larger diameter and surface area than the cylinder 6, there willbe some back flow of fluid in the passageway into the cylinder 3,following the piston 26 as it movesupwardly. As the coil spring 3|reaches its full normal expansion, whereby piston 26 is about to reachits extreme upstroke, the stop 38 strikes the valve 33, thereby movingthis valve upwardly until the annular recess 28 is opened, and thepressure discharge port 31 is closed. Immediately upon the closing ofthe port 31 and the opening of the passageways 5'and the annular recess28, pressure begins to build up again in the cylinder 3. The cycle ofoperation is then repeated. The annular recess 28 and the port 31 maybeso arranged as to require a separate valve for opening and closing eachand several types of port valves may be used.

It is to be understood that while the disclosure presents a practicalworking embodiment of the invention, it is not limited to the specificform shown, but may be modified, altered and changed, in keeping withthe principle involved, andwhich may be said to fall fairly within thescope and meaning of the appended claims.

What is claimed is:

1. A pump of the class described in combination with a Well casing,comprising a collar connected to the lower end of the casing andconstituting a pack-01f; a pressure cylinder in the well casing andseated on said pack-off, said pressure cylinder having one or morepressure inlet passageways and one or more valved fluid dischargepassageways; a pressure tube connected to the upper end of said pressurecylinder and having mounted thereon; a spring mounted on the plunger rodfor moving the plunger rod in one direction; a pump barrel connected tothe lower end of said pressure cylinder and wherein said valved pistonreciprocates; a standing valve in the pump barrel, a mud tube, means forconnecting the mud tube to the pump barrel; and means carried on saidplunger rod for actuating said sliding valve in the opening and closingof said pressure inlet and fluid discharge passageways, said fluiddischarge passageways having ports opening into the bore of the pressurecylinder.

2. A pump of the class described such as deflned and as claimed in claim1, and wherein said fluid discharge passageways'have. ports opening intosaid pressure cylinder for release of gas or air under pressure into thecolumn of fluid being elevated in said fluid discharge passageways; saidpressure inlet passageways in the pressure cylinder having means forconducting the air or gas from the pressure tube through a recess commonto all the pressure inlet passageways and whereby said gas on escapeafter its compression passes from said recess into said dischargepassageways through said ports; said fluid discharge passagewaysincluding elevation ports opening into the lower endot the pressurecylinder below the ports provided for gas or air release, said elevationports being permanently open; 1

3. A pump of the class described in combination with a well casing.comprising a collar-connected to the lower end 01. the casing andconstituting a pack-oil; a pressure cylinder in the well casing andseated on said pack-oft, a pump barrel connected to the lower end of thepressure cylinder, said pressure cylinder having one or more pressureinlet passageways and one or more valved fluid discharge passageways; apressure tube connected to the upper end 01 said pressure cylinder, saidtube being connected to a pumping .sure tube; said means embodying theassemblagev or, a plunger rod, 9. slidable valve mounted thereon, andstop elements for limiting the passage of the slidable valve across saidports; said plunger rod including a plunger piston and a valved pistonmounted in spaced relation thereon, and a spring carried on the upperend of the plunger piston; said plunger piston reciprocable in saidpressure cylinder and said valved piston slidable in said pump barrel,the operation of the pump by said pressure'moving the plunger roddownwardly and by which compression the plunger piston forces the wellfluid upwardly into said fluid elevation ports into the dischargepassageways and simultaneously through said slidable valve releases thegas or air pressure into the column of rising fluid; the pressure onsaid plunger piston being equalized on the downward stroke of theplunger rod, whereupon said spring expands and raises the plunger rod onits upward stroke.

4. A pump of the class described and asclaimed in claim 3 and whereinsaidpressure cylinder is reduced in diameter at its upper end whereby anannular space is formed between ,the pressure cylinder and said wellcasing; the upper end of the pressure cylinder being closed by aremovable plug.

ERNEST C; OVERALL.

